The IDK® Kynurenic Acid ELISA is intended for the quantitative determination of kynurenic acid (Kyna) in urine.

For research use only. Not for use in diagnostic procedures.

For Laboratory Professional Use Only.

This is the RUO version of Immundiagnostik part number K 7735.

Test Principle of the IDK® Kynurenic Acid ELISA

The IDK® Kynurenic Acid ELISA is designed for the quantitative determination of kynurenic acid.

The assay is based on the method of competitive enzyme-linked immunoassays. Samples, standards, and controls are incubated in the wells of a microtiter plate coated with kynurenic acid (antigen), together with a peroxidase-labeled polyclonal anti-kynurenic acid antibody.

During the incubation period, the free target antigen in the sample competes with the antigen immobilized on the wall of the microtiter wells for the binding of the peroxidase-labeled polyclonal antibodies. After a washing step to remove the unbound components, the peroxidase substrate tetramethylbenzidine (TMB) is added. Finally, the enzymatic reaction is terminated by an acidic stop solution.

The color changes from blue to yellow and the absorbance is measured in the photometer at 450 nm. The intensity of the yellow color is inversely proportional to the kynurenic acid concentration in the sample; this means, high antigen concentration in the sample reduces the concentration of antibodies bound to the antigen on the plate and lowers the photometric signal.

A dose-response curve of the absorbance unit (optical density, OD at 450 nm) vs. concentration is generated, using the values obtained from the standards. The presence of kynurenic acid in the samples is determined directly from this curve.